Using sludge from advanced anaerobic digesters to reduce the rate of phosphorous run-off from farm slurry

Reference: 15/SL/02/11
ISBN: 1 84057 795 9
Published Date: 06/11/2015

 The water soluble phosphorus (WSP) content of organic materials is directly related to their potential for P transfer in run-off after land application. Biosolids have a lower WSP than livestock slurry and hence a lower risk of P loss in run-off. The addition of biosolids to livestock slurry at an appropriate rate could reduce the WSP content of the resulting mix due to the binding properties of certain biosolids (as a result of iron-Fe, aluminium-Al and calcium-Ca cations).

A series of experiments were undertaken using a range of biosolids products added to cattle slurry at a variety of mixing rates. The experiments showed that mixing biosolids, or in particular clean water sludge, with slurry did decrease the WSP of the slurry/biosolids mix (compared to slurry). Similarly, the PSYCHIC model predicted a reduction in total catchment P losses, following the addition of the mixed organic material, in comparison to separate applications. 

Price: £20  

The Agronomic and Environmental Impacts of Phosphorus in Biosolids Applied to Agricultural Land: A Review of UK Research

Reference: 11/SL/02/10
ISBN: 1 84057 595 6
Published Date: 13/06/2011

A review of UK research funded over the last 15 years on the potential environmental impacts of phosphorus (P) in biosolids has concluded that biosolids are a valuable, sustainable source of P whose recycling to agricultural land could be expanded in support of sustainable farming, resource protection and provision of ecosystem services. The eutrophication risk associated with biosolid recycling to land is very small provided biosolid types and application rates are matched to minimise P transfer in runoff based on on-site assessment of P loss risk taking account of hydrological connectivity, the degree of soil P saturation and vulnerability to soil erosion.

Price: £17  

Phosphorus Lifecycle Management

Reference: 10/SL/02/9
ISBN: 1 84057 570 0
Published Date: 21/09/2010

Phosphorus is a major reason why UK rivers are not achieving good status under the Water Framework Directive. However, before potentially expensive measures are implemented, the impact of phosphorus on the ecology must be understood. The first phase of this project reviewed the derivation of the phosphorus standard and its justification. Furthermore, to identify suitable measures, where required, it is necessary to identify the main sources of phosphorus to a water body. A series of spreadsheet models was therefore developed to quantify phosphorus sources to water and the main outcome from the project was a fully operational conceptual lifecycle management tool combining environmental quality (chemistry and ecology) and sustainability (economics and carbon emissions) for a number of possible future scenarios demonstrated for the Wensum catchment; which could form the basis for future river basin planning.

Price: £21